斜拉桥传感器优化布点的研究

在振动模态试验中,传感器位置和数目的选择对试验结果的质量有很大的影响。首先回顾了近年来关于传感器最优布点方法的研究。然后以一座三跨预应力混凝土斜拉桥为研究对象,采用有效独立法和基于模态保证标准的算法这两种最优布点算法,对斜拉桥主梁上加速度传感器的最优布点进行了初步的探讨。结果表明:有限元模型和所监控模态振形的阶数对最优传感器布点的选取有较大的影响;用有效独立法对类似的斜拉桥进行优化布点计算时,能得到较为理想的布点方案。

STUDY OF OPTIMAL SENSOR PLACEMENT FOR CABLE-STAYED BRIDGE

In experimental modal testing,the choice of number and location of sensors in the structure has major influence on the results.In extreme cases modes may be completely lost,so sensors should be carefully placed.A survey of recent work on sensor placement is given.A three-span prestressed concrete cable-stayed bridge is studied and the optimal placement of sensors on main beam for bridge health monitoring is discussed.The algorithm based on modal assurance criterion as well as the effective independence algorithm are adopted to determine an optimal(or near optimal) sensor placement.Five criteria are used in the former algorithm to assess the suitability of the chosen measurement locations.It is found that the finite element analysis results and the number of targeted modal shapes influence sensor configurations greatly,and the effective independence algorithm gives more ideal results.